import java.util.*;
import java.util.Stack;

public class Solution3 {
    Stack<Integer> s1 = new Stack<>();
    Stack<Integer> s2 = new Stack<>();
    
    public void push(int node) {
        s1.push(node);
        if(s2.isEmpty()) {
            s2.push(node);
        } else {
            if(s2.peek() < node) {
                s2.push(s2.peek());
            } else {
                s2.push(node);
            }
        }
    }
    
    public void pop() {
        s1.pop();
        s2.pop();
    }
    
    public int top() {
        return s1.peek();
    }
    
    public int min() {
        return s2.peek();
    }
}
